If you are a Small Business customer, find additional troubleshooting and learning resources at the Support for Small Business site.

After you install Windows XP Service Pack 3 (SP3), some programs may seem not to work. By default, Windows Firewall is enabled and blocks unsolicited connections to your computer. This article discusses how to make an exception and enable a program to run by adding it to the list of exceptions. This procedure enables the program to work as it did before the service pack was installed.

To help provide security for your Windows XP SP3-based computer, Windows Firewall blocks unsolicited connections to your computer. Sometimes you might want to make an exception and allow for someone to connect to your computer. For example, the following scenarios describe occasions when you might want someone to be able to connect to your computer:

You are playing a multiplayer game over the
Internet.

You are expecting to receive a file that is sent through
an instant message program.

After you install Windows XP SP3, client programs may not
successfully receive data from a server. The following are some examples:

An FTP client

Multimedia streaming software

New mail notifications in some e-mail programs

Or, server applications that are running on a
Windows XP SP3-based computer may not respond to client requests. The following are
some examples:

Windows Security Alert

Resolution

To work correctly, some programs and games must receive
information over the network. The information enters your computer through an inbound port. For Windows Firewall to allow for this information to enter,
the correct inbound port must be open on your computer. If you recognize the name of the program, and you want to allow for the program to function as usual, click Unblock in the Windows Security Alert dialog box.

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Advanced users section

This section is intended for advanced computer users. If you are not comfortable with advanced troubleshooting, you might want to ask someone for help or contact support. For information about how to do this, visit the following Microsoft website:

If your program still does not seem to work after you add the program to the list of exceptions, or if you cannot locate the program in step 5 of the previous section, you can open a port manually.

Important Before you can add a port or ports manually, you have to identify the ports that are used by the program. A reliable method for identifying the ports that are used by the program is to contact the vendor. If you cannot do this, or if a list of ports that are used by the program is not available, you can use Netstat.exe to identify the ports that are used by the program.

Note If the program in question is running as a service, add the /svc switch to list the services that are loaded in each process:

tasklist /svc > tasklist.txt

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In Tasklist.txt, locate the program that you are
troubleshooting. Note the process identifier (PID) for the process.

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In Netstat.txt, note any entries that are associated
with the process identifier. Note the protocol that is used (TCP or
UDP).

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Important If the program uses more than one port, repeat this procedure to identify the additional ports that are used by the program. If you repeat the procedure and the port number that the program uses continues to change, add a program-based exception or contact the vendor of the program.

If you cannot identify the ports that are used by the program, you can open a port manually. To identify the specific port number to open, contact the product vendor or see the product user documentation. After you identify the port number that you want to open, follow these steps:

Click Start, and then click Run.

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Type wscui.cpl, and
then click OK.

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Click Windows Firewall.

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On the Exceptions tab, click Add Port.

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In the Add a Port dialog box, type the name that you want to use for the port exception in the Name box, type the
number of the port that you want to open in the Port number
box, and then click either TCP or UDP.

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To view or set the scope for the port exception, click
Change Scope.

Select the scope options that you want to use for this exception, and then click OK.

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On the Exceptions tab, notice that the new service is listed. To enable the port, check the box next to the service, and then click OK.

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For more information about how to configure Windows Firewall, click the following article number to view the article in the Microsoft Knowledge Base:

Needed so that a Windows Server 2003
eTrust 7.0 server can remotely test logon to a Windows XP SP3-based client

Computer Associates eTrust 7.0

Needed so that a Windows Server 2003 eTrust
7.0 server can remotely install the client eTrust software on Windows XP
SP3-based computers. Resolved by setting the following to 0 and then rebooting:
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows
NT\RPC\RestrictRemoteClients (DWORD value)

Microsoft provides third-party contact information to help you find technical
support. This contact information may change without notice. Microsoft does not
guarantee the accuracy of this third-party contact information.

Microsoft provides third-party contact information to help you find technical
support. This contact information may change without notice. Microsoft does not
guarantee the accuracy of this third-party contact information.

For information about your hardware manufacturer, visit the following website:

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.